Fire alarm



1,630,550 1927' J. cs. TREMAIN FIRE ALARM Filed Auz. 1, 1923 INVENTOR.

BY W

AT ORNEY.

Patented May 31, 1927,.

UNITED STATES 1,630,55t PATENT OFFICE.

JAMES G. TREMAIN, CF PORT HURON, MICHIGAN, ASSIGNOR OF ONE-HALF T JOSEPH TBEMAIN, OI" DETROIT, MICHIGAN.

FIRE ALARM.

Application filed August 1, 1923.

This invention relates to mechanical means, as distinguished from electrical, for announcing a predetermined temperature at the point where the device is located, and its object is to provide a device of this character which shall always be in working condition, which can be secured in any desired position, which can. be manufactured at low cost, and which can be installed by even the most unskilled labor.

This invention consists of an alarm comprising a clockwork and a sounder to be actuated thereby, controlling means to pre vent the clockwork from operating, and a fusible device to hold the controlling means in operative position.

It also consists in means comprising a part of the sounding device to secure this alarm in position.

It further consists of the details of construction illustrated in the accompanying drawing and particularly pointed out in the claims.

In the accompanying drawing, Fig. 1 isa plan of this improved fire alarm with the base removed. Fig. 2 is a section on the line 2-2 of Fig. 1.

Similar reference characters refer to like parts throughout the several views.

Fire alarms comprising electric batteries, signals, circuits and switches whose contacts are held apart by fusible material have been suggested but are objectionable because the circuits are apt to be broken and the batteries run down and must be replaced. They are often forgotten so that the alarms be come useless. The present invention is purely mechanical and may be left untested for years. It consists of a small spring driven clockwork including a hammer, a

' stop device for the clockwork and an anvil so attached to a part of the building that the vibrations of the sounder will be transmitted thereby.

Attached to a ceiling, wall or any other part of a building is a narrow base 1 to which a resilient metal plate 2 is attached. A screw 3 may pass through this plate and through the base 1 into the part 4 of the building. It is essential that this part of the building may vibrate freely and I therefore prefer some wooden portion of a floor between joists or a portion of a wall between studding, but any other part of the building which is free to vibrate may be Serial no. 655,042.

used. The clockwork comprises a plate of sheet metal bent to form the sides 5 which are connected by a top 6. The sides may be attached to the base 1 in any desired manner and are perforated to receive the main shaft 7 on which are mounted a clockspring 8, a ratchet wheel 9 and a main gear 10 which is driven by the ratchet wheel 9 through the pawl 11 held inward by the spring 12. One end of the clock-spring 8 attaches to the pin 14.

A second shaft 15 carries the small gear 16 and the escapement wheel 17 which is engaged by the escapement 18 on the shaft 19. A rod 20 attached to this shaft carries the hammer 21 which acts as a pendulum of the escapement and itsanvil 22 may be a part of the screw 23 which assists to secure the base 1 to the part 4 of the building.

The plate 2 may also be secured to the base 1 by means of a screw 24 and it is normally held in the position shown in Fig. 2, with its free end in the path of the teeth of the escapement wheel 17 by a small block 23 of fusible material. So long as this material remains in place the clockwork cannot operate and the hammer 21 is stationary. But as soon as the atmosphere surrounding the block 23 or the base 1 becomes sutficiently hot to melt this block the plate 2 assumes the dotted line position of Fig. 2 and releases the escapcment. The clockwork will now operate to vibrate the hammer 21 which produces a loud noise by tapping the anvil 22. As this anvil is connected to a ceiling or wall or other part of the building which can act as a sounding board and sound conductor, this noise can be heard in even distant parts of the building and the occupants are thus warned of the unusual heat adjacent this fire alarm.

The fusible block 23 can be easily replaced and the clockwork rewound by the button 25. Any other desirable clockwork may be substituted for that shown, which is of well known design, so long as the anvil for the hammer 21 is rigidly attached to some permanent part of the building which is sufficiently free to vibrate to transmit the sounds of the tapping of this hammer.

1. A fire-alarm for buildings comprising a clockwork and a hammer adapt-ed to be vibrated thereby, an anvil for said hammer secured to such a portion of the building as hold said plate in operative position, said anvil serving to secure the alarm in position.

3. In a fire-alarm for buildings, a hammer and a spring driven mechanism to vibrate it, an anvil attached to a Wooden portion of the building which is adapted to transmit vibrations, and a block of fusible material to normally prevent the operation of the 90 hammer.

J AMES G. TREMAIN. 

